Cargo bars are well known as a means of supporting cargo in transportation systems. Generally they comprise inner and outer telescoping tubes which can be extended against walls of an interior of a cargo compartment such as those found in a truck or airplane. However, prior cargo bars had a low maximum weight tolerance due to weak or insecure focal points.
The following exemplary cargo bars are illustrative of what is known in the art: a first prior art device, depicted in FIG. 17 and described in U.S. Pat. No. 5,833,414 to Feldman; a second prior art device, depicted in FIG. 18 and described in U.S. Pat. No. 5,947,666 to Huang; and a third prior art device, depicted in FIG. 19 and described in U.S. Patent Application Publication Number 2008/0210915 to Ruan.
The prior art cargo bar device depicted in FIG. 17 (Feldman) generally comprises inner and outer tubular members, and a gear rack. The gear rack is attached to the inner and outer tubular members. A housing surrounding the inner and outer tubular members has a lever for extending the inner tubular member from the outer tubular member. This extension is accomplished by pivoting the lever, which rotates a gear whose teeth are connected to the lever, the gear thereby being forced against the teeth of the gear rack, moving the inner tubular member. Once the bar is fully extended, the lever may lock into place, allowing the bar to be secured in place against two walls. One disadvantage to this system is that the cargo bar's securing function is only as strong as its weakest point. As the gear rack is attached at a small number of points to the cargo bar, this creates a point of weakness, since the attachment points between the cargo bar and the gear rack must bear the entire weight load of the cargo bar.
The prior art cargo bar device depicted in FIG. 18 (Huang) also generally comprises outer and inner tubular members, the inner tubular member being slidably inserted within the outer tubular member. A housing with a lever having a gear surrounds the inner and outer tubular members. The inner tubular member has notches for interacting with the teeth of the gear. This allows the bar to be extended in a similar fashion as the Feldman device. However, in comparison to the Feldman patent, this device suffers from a different but related problem of not having a strong point of attachment between the gear and the surface upon which the gear teeth are acting.
The prior art cargo bar device depicted in FIG. 19 (Ruan) is similar to the previously described bars, comprising an inner and outer tubular casing, the inner tubular casing having angled ridges, and a handle with teeth for engaging the inner tubular casing. However, the Ruan device moves the inner bar utilizing a minimal number of teeth. This creates a weak point, as the minimal number of teeth must bear the entire weight of the cargo bar load.
Therefore, it is an object of this application to provide a high weight tolerance cargo bar. It is a further object of this application to provide a cargo bar having easy fastening and extending features. It is a further object of this application to provide a cargo bar having a secure extension feature.